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Whole-slide imaging was used in assessment of DNA content
of Feulgen-stained sections of Barrett esophagus with dysplasia
[ 5 ]. In addition, whole-slide imaging has been reported in the
assessment of HER2 expression in tissue microarray sections [ 6 –
8 ]. The assessment of HER2 is a common practice in predicting
the use of target therapy in esophageal adenocarcinoma (see
Chapters 5 and 11 ). Thus, whole-slide imaging has also potential
clinical and research applications of testing HER2 by immuno-
chemistry or in situ hybridization in esophageal adenocarcinoma.
There are barriers to adoption of whole-slide imaging in clini-
cal and research works. The major obstacles include the current
high cost of the scanner and the time needed to scan a slide. There
are also technical problems such as the technical difficulties in
obtaining good images with thick cytology smears. In addition, for
clinical application, we need validation of the procedure, proper
training of staff, and attention to the security, privacy, and work-
flow issues. Furthermore, we need to consider the impact of the
workforce in a pathology laboratory as well as the availability of
backup and disaster recovery procedures.
There are many models of equipment (scanners) used to
achieve whole-slide imaging available in the market. At present,
there are more than ten different brands of scanners in the market.
In the past, imaging scanning equipment could scan one or only a
few slides in a run. Newer models have the capacity to hold and
scan hundreds of slides at one time. This allows smooth running of
the workflow for diagnostic and research laboratory. In this chap-
ter, we would outline the principle of use of one of the scanners
that we can use to scan hundreds of slides for research and clinical
applications in esophageal adenocarcinoma.2 Materials
A well-prepared slide is important for the success of scanning. The
slides should be in clean and good condition (see Note 1).- Make sure that the slides have no dirt, fingerprints, excessive
adhesion, glue, or scratches around. - All the slides for scanning should have coverslips, firmly labeled
and are not wet. - Some slides may have pen or dirt marking and could be resolved
by cleaning the slide with a cotton cloth or tissue towel with
alcohol or xylene. If we use the alcohol or xylene (for cleaning
of permanent marker, dirty glue, etc.), it will achieve better
results. However, the slides should be cleaned well ahead to
allow time for drying. - With excessive glass coverslip on slide, it can be resolved by
trimming the slide edge with razor blade.
Alfred K. Lam and Melissa Leung